Multi-component fibers and uses thereof

ABSTRACT

A bicomponent fiber comprises a core component formed from a rate-sensitive material; and a sheath component surrounding the core component, the sheath component being formed from a non-rate-sensitive polymer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 62/756,659, filed Nov. 7, 2018, the entirety of which is incorporated by reference herein.

FIELD

The invention is generally related to multicomponent fibers, fabrics, and uses thereof, and, more specifically, to multicomponent fibers comprising a rate-sensitive material.

BACKGROUND

Fabrics are persistently subjected to environmental challenges affecting the deterioration and/or lifespan of the fabric. Certain activities, such as running, washing, or even normal wear or use, expose fabrics to various stresses. Such stresses can include stretching and load bearing. Insults from the surrounding environment, such as ultraviolet radiation or heat exposure from the sun, can also damage a fabric. In many instances, the outcomes observed from such challenges, including decreased lifespan, are a result of how well the fibers within the fabric respond to the challenges. Thus, fibers having properties to resist deterioration and increase the lifespan of fabrics are needed. Fibers providing improved performance to fabrics and other articles are also desired.

SUMMARY

Textile fibers, fabrics, and articles are described herein. Generally, the fibers are multicomponent fibers, such as bicomponent fibers. In some embodiments, these fibers can provide one or more advantages over other fibers and can be incorporated into fabrics and/or articles in need thereof. For example, fibers described herein can be used to form fabrics with enhanced properties that increase the quality, performance, and lifespan of the fabric. Similarly, fabrics described herein can be used to form articles with enhanced properties that increase the quality, performance, and lifespan of the article. Properties such as enhanced colorfastness, tear resistance, breathability, elasticity, softness, flexibility, durability, resiliency, and/or antimicrobial properties can be achieved using fibers and fabrics described herein.

In some embodiments, a bicomponent fiber described herein comprises a core component formed from a rate-sensitive material and a sheath component surrounding the core component. The sheath component is formed from a non-rate-sensitive polymer. In some embodiments, the rate-sensitive material is a thermoplastic polyester elastomer. In some cases, the rate-sensitive material is present in the fiber in an amount of 70-85 wt. %, based on the total weight of the fiber. The rate-sensitive material, in some cases, is temperature-sensitive and/or pressure-sensitive, as described further hereinbelow. In other cases, the rate-sensitive material comprises a dilatant material. Additionally, in some instances, the non-rate-sensitive material is present in the fiber in an amount of 15-30 wt. %, based on the total weight of the fiber. The non-rate-sensitive polymer, in some cases, comprises a synthetic polymer, a natural polymer, or a combination thereof.

In addition to fibers, fabrics and other articles are also described herein. Such fabrics and articles can comprise, include, or be at least partially formed from fibers described herein, including multicomponent fibers described herein. For example, in some embodiments, a fabric or other article comprises or is at least partially formed from a bicomponent fiber comprising a core component formed from a rate-sensitive material and a sheath component surrounding the core component. Moreover, in some cases, an article is formed from a fabric according to the present disclosure. Such an article may be, for instance, an article of clothing, a shoe or other footwear, a chair or seat or other article furniture, or a bag or other container. Other articles can also be formed from fibers and fabrics described herein.

These and other embodiments are described in detail in the detailed description that follows.

DETAILED DESCRIPTION

Embodiments described herein can be understood more readily by reference to the following detailed description and examples. Elements and compositions described herein, however, are not limited to the specific embodiments presented in the detailed description and examples. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptations will be readily apparent to those of skill in the art without departing from the spirit and scope of the invention.

In addition, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a stated range of “1.0 to 10.0” should be considered to include any and all subranges beginning with a minimum value of 1.0 or more and ending with a maximum value of 10.0 or less, e.g., 1.0 to 5.3, or 4.7 to 10.0, or 3.6 to 7.9.

All ranges disclosed herein are also to be considered to include the end points of the range, unless expressly stated otherwise. For example, a range of “between 5 and 10” should generally be considered to include the end points 5 and 10.

Further, when the phrase “up to” is used in connection with an amount or quantity, it is to be understood that the amount is at least a detectable amount or quantity. For example, a material present in an amount “up to” a specified amount can be present from a detectable amount and up to and including the specified amount.

As used herein, the term “fiber” refers to a textile fiber, yarn, or filament. Similarly, “fibers” can refer collectively to fibers, yarns, and filaments.

In one aspect, fiber compositions are described herein. In some cases, such a composition comprises a multicomponent fiber. A multicomponent fiber, in some preferred embodiments, is a bicomponent fiber. A multicomponent or bicomponent fiber described herein can have any structure or configuration not inconsistent with the objectives of the present disclosure. For example, in some instances, a fiber described herein has a core-sheath configuration, island-in-the-sea configuration, or other configuration having a core or interior component and a sheath or exterior component. In general, the core or interior component can comprise one or more individual cores formed from one or more materials that are the same or different from one another. Similarly, the sheath or exterior component can comprise or be formed from one or more materials, where the sheath or exterior component surrounds or substantially surrounds the outer surface of the one or more core. Thus, the core or interior component can be covered or surrounded by or embedded within the sheath or other exterior component.

Fibers described herein, in some preferred embodiments, are bicomponent fibers comprising a core and a sheath. In such cases, the sheath can surround the core axially. For example, the core of a bicomponent fiber can be axially centered, or approximately axially centered, along the length of the fiber, and the sheath can encompass, surround, or cover the core. The sheath can particularly encompass, surround, or cover the core along the length of the fiber. In some cases, the sheath is in direct contact with the core, with no other material layers in between the sheath and core. Moreover, in some embodiments, the sheath covers at least 85%, at least 90%, or at least 95% of the surface of the core along the length of the fiber. In some cases, the sheath covers at least 98% or at least 99% of the surface of the core along the length of the fiber.

As described above, the core of a bicomponent fiber described herein can comprise or be formed from a rate-sensitive material. Such a “rate-sensitive” material can have a first property whose value changes non-linearly with a second property, the second property being a rate or frequency. In some embodiments, for example, a rate-sensitive material includes or comprises a rate-sensitive thermoplastic elastomer. Such materials exhibit different stiffness values at different rates or frequencies. For instance, rate-sensitive materials can be soft and flexible at lower rates or frequencies, but stiffen or harden under higher rates or frequencies. As described herein, such rate-sensitivity can provide increasing stability and performance under certain conditions of use of a fiber, fabric, and/or article described herein. One non-limiting example of a rate-sensitive material is a polyester elastomer, such as D3O®, a DuPont™ Hytrel® thermoplastic polyester elastomer (TPC-ET). In some embodiments, the rate-sensitive material is a polyester elastomer comprising a phase that is “hard” at room temperature, but becomes fluid upon heating, and another phase is a softer material that is rubbery at room temperature. In some embodiments, the TPE-ETs is a block copolymer having a general structure of (A-B)n, where A and B are the hard and soft material blocks, respectively, and n is a positive integer such as any of 1 through 10,000. As evidenced by the D30® line of TPE-ET, the ratio of hard and soft blocks in the polymer can be altered to provide different levels of “rate-sensitivity”. In some cases, the (TPE-ET) are block copolymers that combine the favorable characteristics of vulcanized rubber with the easy processability of thermoplastics for toughness, tear and flex fatigue resistance over a wide temperature range.

The rate-sensitivity of a rate-sensitive material described herein, in some cases, is further influenced by an operational parameter. For example, in some embodiments, a rate-sensitive material can be temperature-sensitive. A change in temperature, in some cases, can affect the characteristics or properties of the rate-sensitive material. Such rate-sensitive materials that are temperature-sensitive can exhibit a significant shift in rate-sensitivity upon a change in temperature, and in some cases, upon a nominal change in temperature. For example, an increase or decrease in temperature can change the melt viscosity at certain shear rates. Thus, characteristics or properties of the rate-sensitive material, including mechanical properties, thermal properties, and electrical properties, in some cases, can vary at different temperatures in rate-sensitive materials.

In other embodiments, a rate-sensitive material can be pressure-sensitive. For example, a change in pressure or load, in some cases, can affect the characteristics or properties of the rate-sensitive material. Such rate-sensitive materials that are pressure-sensitive can exhibit a significant shift in rate-sensitivity upon a change in pressure or load, and in some cases, upon a nominal change in pressure or load. For example, an increase or decrease in pressure or load can change the flow length at certain melt flow rates. Thus, characteristics or properties, including mechanical properties, thermal properties, and electrical properties, in some cases, can vary at different values of pressure or load in rate-sensitive materials.

Rate-sensitive materials exhibit a variety of desirable characteristics or properties at different rates or frequencies. Non-limiting examples of desirable characteristics or properties that can vary in rate-sensitive materials include adhesion, water absorption, humidity absorption, hydrolysis resistance, tensile strength, compression strength, impact strength, fatigue resistance, heat absorption, light reflection, colorfastness, abrasion-resistance, friction resistance, tear resistance, flex-fatigue resistance, creep resistance, impact resistance, chemical resistance, heat-aging resistance, wet-squeak resistance, stress-cracking resistance, crack propagation resistance, ultraviolet radiation resistance, nuclear radiation resistance, breathability, gas permeability, ductility, elasticity, brittleness, conduction, shrinkage, flammability, antimicrobial properties, hardness, toughness, softness, flexibility, resilience, porosity, rigidity, density, and others. It should be understood that any rate-sensitive material, not inconsistent with the goals of the present disclosure can be used. Moreover, selection of certain characteristics or properties and/or profiles in rate-sensitive materials can vary by use and/or application of fibers, fabrics, and/or articles described herein.

Further, in some cases, a rate-sensitive material described herein is a composite material that includes a mixture, blend, or combination of a plurality of distinct materials. In some such instances, for example, the rate-sensitive material includes an “active” or particularly rate-sensitive component combined with one or more other “inactive” or substantially non-rate-sensitive components. In some embodiments, the rate-sensitive material of a fiber described herein comprises or is at least partially formed from a dilatant or shear thickening fluid. For example, such a dilatant can be present in the rate-sensitive material in an amount of about 15-40% wt %, based on the total weight of the rate-sensitive material. The rate-sensitive material, in some instances, comprises dilatant in an amount of at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, or at least 40% wt. %, based on the total weight of the rate-sensitive material. In some cases, the rate-sensitive material comprises a dilatant in an amount of about 5-80%, 10-75%, 10-50%, 10-40%, 15-45%, 15-50%, 15-60%, 15-70%, or 15-80% wt %, based on the total weight of the rate-sensitive material.

The overall rate-sensitive material or the rate-sensitive component or the core component of a fiber described herein can be present in the fiber in any amount not inconsistent with the objectives of the present disclosure. For instance, in some embodiments, the rate-sensitive material or component or core component is present in the fiber in an amount of about 10-85 wt. %, based on the total weight of the fiber. In some cases, the rate-sensitive material or component or core component is present in the fiber in an amount of up to 20 wt. %, up to 30 wt. %, up to 40 wt. %, up to 50 wt. %, up to 60 wt. %, up to 70 wt. %, up to 75 wt. %, up to 80 wt. %, or up to least 85 wt. %, based on the total weight of the fiber. In some cases, the rate-sensitive material or component or core component is present in the fiber in an amount of less than 50 wt. %, less than 40 wt. %, less than 30 wt. %, less than 20 wt. %, less than 15 wt. %, less than 10 wt. %, or less than 5 wt. %, based on the total weight of the fiber. In some instances, the rate-sensitive material or component or core component is present in the fiber in an amount of about 5-90 wt. %, 5-80 wt. %, 5-70 wt. %, 5-60 wt. %, 5-50 wt. %, 10-80 wt. %, 10-70 wt. %, 10-60 wt. %, 10-50 wt. %, 10-40 wt. %, 10-30 wt. %, 10-20 wt. %, 15-60 wt. %, 15-50 wt. %, 15-45 wt. %, 15-40 wt. %, 15-35 wt. %, 15-30 wt. %, 20-60 wt. %, 20-50 wt. %, 20-40 wt. %, 30-80 wt. %, 30-70 wt. %, 30-60 wt. %, 30-50 wt. %, 30-40 w. %, 40-80 wt. %, 40-70 wt. %, 40-60 wt. %, 40-50 wt. %, 50-90 wt. %, 50-70 wt. %, 50-60 wt. %, 60-90 wt. %, 65-90 wt. %, 65-85 wt. %, 70-90 wt. %, 75-85 wt. %, or 80-90 wt. %, based on the total weight of the fiber.

As described above, the sheath or exterior component of a bicomponent or other multicomponent fiber described herein can comprise or be primarily or fully formed from a non-rate-sensitive material. In some cases, the sheath or other exterior component is formed from a non-rate-sensitive polymer. Any non-rate-sensitive polymer not inconsistent with the objectives of the present disclosure can be used. For example, in some embodiments, a non-rate-sensitive polymer comprises a natural or naturally-occurring polymer, such as an animal-based polymer or a plant-based polymer. Non-limiting examples of animal-based polymers (polymers produced by and isolated from an animal) include silks, wools, and hairs, such as from a silkworm, spider, alpaca, goat, sheep, lamb, camel, or rabbit. A plant-based polymer (a polymer produced by and isolated from a plant) can include a polymer derived from one or more parts of a plant, including the seed, root, stalk, bark, leaf, vegetable, and/or fruit of the plant. Non-limiting examples of plant-based polymers include cotton, hemp, bamboo, sisal, flax, jute, and soy.

In other embodiments, a non-rate-sensitive polymer comprises a synthetic polymer (a polymer that is man-made from non-polymer starting materials) or semisynthetic polymer (a polymer that is manufactured by humans from a naturally occurring polymer starting material, such as described above). A synthetic or semisynthetic polymer, in some cases, comprises a thermoplastic or elastomer. Non-limiting examples of synthetic and semisynthetic polymers (or fibers) include polyesters; spandex and other polyether-polyurea copolymers; polyacrylics; nylons and other polyamides; polyethylene, polypropylene, polybutylene, and other polyolefins; modal, lyocell, and other rayons or regenerated celluloses; so-called acetates; and polylactic acid (PLA). It should be understood that any synthetic or semisynthetic polymer not inconsistent with the objectives present disclosure is contemplated.

In some embodiments, the non-rate-sensitive material of a fiber described herein is present in the fiber in an amount of up to 40 wt. %, up to 35 wt. %, up to 30 wt. %, up to 25 wt. %, up to 20 wt. %, or up to 15 wt. %, based on the total weight of the fiber. For example, a non-rate sensitive material, in some instances, is present in the fiber in an amount of about 10-40 wt. %, 10-35 wt. %, 10-30 wt. %, 10-25 wt. %, 10-20 wt. %, 15-40 wt. %, 15-35 wt. %, 15-30 wt. %, 20-40 wt. %, 20-35 wt. %, 25-40 wt. %, or 25-35 wt. %, based on the total weight of the fiber.

Moreover, the overall sheath or other exterior component can be present in a fiber described herein in any of the amounts described in the preceding paragraph with respect to the non-rate-sensitive material. That is, in some embodiments, the sheath or other exterior component of a fiber described herein is present in the fiber in an amount of up to 40 wt. %, up to 35 wt. %, up to 30 wt. %, In some cases, the sheath component or other exterior component is present in the fiber in an amount of about 10-40 wt. %, 10-35 wt. %, 10-30 wt. %, 10-25 wt. %, 10-20 wt. %, 15-40 wt. %, 15-35 wt. %, 15-30 wt. %, 20-40 wt. %, 20-35 wt. %, 25-40 wt. %, or 25-35 wt. %, based on the total weight of the fiber.

Fibers described herein, such as bicomponent fibers, can permit conventional or traditional fiber and/or fabric processing to be used for fibers that, unconventionally, also exhibit rate-sensitive behavior, such as rate-sensitive behavior described above. As described above, a bicomponent fiber described herein can include a rate-sensitive material as the core, and a traditional material as the sheath. The sheath material (e.g., polyester) could generally be selected based on a desired application or end use of the fiber or of a fabric formed from the fiber. For example, to replace or improve upon a convention nylon fiber or fabric, a multicomponent fiber described herein could be formed in which the sheath or other outer component is nylon. Similarly, to replace or improve upon a conventional polyester fiber or fabric, the sheath or other exterior component of a fiber described herein could be polyester. Multicomponent fibers having such a construction can present a seemingly “conventional” exterior surface to the external environment of the fibers, thus permitting the use of conventional dyeing procedures or other fiber and/or fabric processing procedures. Additionally, multicomponent fibers described herein generally shield or sequester the skin of a user from the rate-sensitive material of the fiber.

A fiber described herein can also be coated with one or more additional materials to provide a desired property. In some cases, for instance, a fiber can be coated with a fluorocarbon such as polytetrafluoroethylene. A fiber described herein can also include one or more additives, including polymer additives, which can provide heat absorption and/or heat reflectivity properties. Non-limiting examples of thermally conductive additives which may be used in some embodiments described herein include ceramics such as aluminum nitride and/or boron nitride ceramics, metals such as aluminum or copper, and nanoscale carbon materials such as carbon fibers, carbon nanotubes, and graphite nanoplatelets. Additives comprising thermochromic or photochromic pigment and dye materials may also be used. Such pigment and dye materials can change color in response to heat, light, moisture, and/or pressure. It is also possible to incorporate one or more antimicrobial or antifungal materials into or onto a fiber described herein. Non-limiting examples of antimicrobial or antifungal materials that may be used in some embodiments described herein include inorganic, organic, and/or metal-containing antimicrobial materials such as materials comprising silver, copper, and/or zinc, and quaternary silane-based antimicrobial materials. An additive can also be used to provide a “smart” fabric or textile.

Moreover, a fiber described herein can have any size, shape, and/or denier not inconsistent with the objectives of the present invention.

Fibers described herein can be formed in any manner not inconsistent with the objectives of the present disclosure. For example, in some cases, a multicomponent fiber described herein is formed by extrusion, melt spinning, dry spinning, wet spinning, or gel spinning. Other known methods of making fibers may also be used. Moreover, as understood by one of ordinary skill in the art, a multicomponent fiber such as a bicomponent fiber described herein, in some instances, can be formed through an extrusion process using an appropriate die.

In another aspect, fabrics are described herein. Such fabrics comprise multicomponent fibers described above. For example, in some embodiments, a fabric described herein comprises a bicomponent fiber comprising a rate-sensitive material in an interior region of the fiber and a non-rate-sensitive material in an exterior region of the fiber. A fabric comprising multicomponent fibers, as described above, can be formed from a blend of said multicomponent fibers and other fibers that are not multicomponent fibers according to the present disclosure. The relative amounts of multicomponent fibers according to the present disclosure, and other fibers not according to the present disclosure, are not particularly limited. That is, any desired amount of multicomponent fiber of the present invention may be used to form a fabric. In some cases, for instance, a fabric comprises 1-99 wt. %, 1 wt %, 3 wt %, 5 wt %, 10 wt %, 15 wt %, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, 65 wt%, 70 wt%, 75 wt %, 80 wt %, 85 wt %, 90 wt %, 95 wt %, or 99 wt % bicomponent fiber described herein, based on the total weight of the fabric. In other embodiments, all of the fibers used to form a fabric are multicomponent fibers according to the present disclosure.

Additionally, a fabric described herein can be made or formed in any manner not inconsistent with the objectives of the present disclosure. In some cases, for example, a fabric described herein is made by knitting, weaving, felting, knotting, and/or crocheting. Further, in some cases, a fabric described herein exhibits characteristics or properties based on the composition of the bicomponent fiber as well as the method of making the fabric. Such fabrics, in some embodiments, can have specific utility. For example, a fabric having a desired woven or knit structure, combined with the rate-sensitive properties and other properties described herein, can be used for applications in which such specific woven or knit structures are desired. Non-limiting examples of such uses include clothing, footwear, and seating surfaces.

In still another aspect, articles are described herein. In particular, such articles comprise or are formed at least partially from multicomponent fibers and/or related fabrics described above. For example, in some embodiments, an article described herein comprises or is at least partially formed from a bicomponent fiber having a core component formed from a rate-sensitive material and a sheath component formed from a non-rate-sensitive component. It is further to be understood that an article described herein can comprise or be formed from a blend or combination of fibers and/or fabrics described herein with other materials (such as other fibers or other fabrics) that are not necessarily according to the present disclosure. Moreover, such an article can nevertheless exhibit one or more rate-sensitive properties, as well as properties imparted by other components of a multicomponent fiber described herein. Non-limiting examples of articles contemplated herein include clothes, footwear, furniture or upholsteries or seating surfaces, bags or other containers, sporting goods, and home goods. More generally, any article comprising or formed from textiles, fabrics, or fibers not inconsistent with the goals of the disclosure is contemplated. 

1. A bicomponent fiber comprising: a core component formed from a rate-sensitive material; and a sheath component surrounding the core component, the sheath component being formed from a non-rate-sensitive polymer.
 2. The fiber of claim 1, wherein the rate-sensitive material is present in the fiber in an amount of 70-85 wt. %, based on the total weight of the fiber.
 3. The fiber of claim 1, wherein the non-rate-sensitive material is present in the fiber in an amount of 15-30 wt. %, based on the total weight of the fiber.
 4. The fiber of claim 1, wherein the rate-sensitive material is temperature-sensitive and/or pressure-sensitive.
 5. The fiber of claim 1, wherein the rate-sensitive material comprises a dilatant material.
 6. The fiber of claim 1, wherein the non-rate-sensitive polymer comprises a synthetic polymer.
 7. The fiber of claim 1, wherein the non-rate-sensitive polymer comprises a natural polymer.
 8. The fiber of claim 1, wherein the non-rate-sensitive polymer comprises a polyamide, polyester, polyethylene, polypropylene, polybutylene, polyacrylic, cotton, wool, silk, or a combination of two or more of the foregoing.
 9. The fiber of claim 1, wherein the rate-sensitive polymer comprises a thermoplastic polyester elastomer.
 10. A fabric comprising the bicomponent fiber of claim
 1. 11. An article comprising the bicomponent fiber of claim
 1. 